You can use any light cycle you want, but the more light the better. Even 18/6 is perfectly acceptable.

For your next seeds look into easy to grow strains like Nirvana White Widow, Northern Lights #5 or Pure Power Plant (PPP) for example. Those are non-autoflowering with good yields and plenty of potency.

Don't get too hung up on the times. I think the plants are taking longer to mature from the problems you had earlier. The times the breeders give are for ideal conditions so don't worry about it. Just get things the way they want them, and let 'em do their thing :thumbsup: